Private ds As New DataSet
    Private kunden As New DataTable("Kunden")
    Private branchen As New DataTable("Branchen")
    Private bsk As BindingSource
    Private bsb As BindingSource
 
    Private Sub Test()
        Dim kpck(0) As DataColumn
        kpck(0) = kunden.Columns.Add("KundenId", GetType(Integer))
        kunden.Columns.Add("BranchenId", GetType(Integer))
        kunden.Columns.Add("Name", GetType(String))
        kunden.PrimaryKey = kpck
        Dim dr As DataRow
 
        dr = kunden.NewRow()
        dr("KundenId") = 1
        dr("BranchenId") = 1
        dr("Name") = "Firma1"
        kunden.Rows.Add(dr)
 
        dr = kunden.NewRow()
        dr("KundenId") = 2
        dr("BranchenId") = 1
        dr("Name") = "Firma2"
        kunden.Rows.Add(dr)
 
        dr = kunden.NewRow()
        dr("KundenId") = 3
        dr("BranchenId") = 2
        dr("Name") = "Firma3"
        kunden.Rows.Add(dr)
 
        dr = kunden.NewRow()
        dr("KundenId") = 4
        dr("BranchenId") = 2
        dr("Name") = "Firma4"
        kunden.Rows.Add(dr)
 
        dr = kunden.NewRow()
        dr("KundenId") = 5
        dr("BranchenId") = 3
        dr("Name") = "Firma5"
        kunden.Rows.Add(dr)
 
        ds.Tables.Add(kunden)
        bsk = New BindingSource(ds, "Kunden")
        DataGridView1.DataSource = bsk
 
 
        Dim bpck(0) As DataColumn
        bpck(0) = branchen.Columns.Add("BranchenId", GetType(Integer))
        branchen.Columns.Add("Name", GetType(String))
        branchen.PrimaryKey = bpck
 
        dr = branchen.NewRow()
        dr("BranchenId") = 1
        dr("Name") = "Branche1"
        branchen.Rows.Add(dr)
 
        dr = branchen.NewRow()
        dr("BranchenId") = 2
        dr("Name") = "Branche2"
        branchen.Rows.Add(dr)
 
        dr = branchen.NewRow()
        dr("BranchenId") = 3
        dr("Name") = "Branche3"
        branchen.Rows.Add(dr)
 
        ds.Tables.Add(branchen)
        bsb = New BindingSource(ds, "Branchen")
 
        ComboBox1.DisplayMember = "Name"
        ComboBox1.ValueMember = "BranchenId"
        ComboBox1.DataBindings.Add("SelectedValue", bsk, "BranchenId")
        ComboBox1.DataSource = bsb
 
    End Sub

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